This invention relates to buffer magazines for installations supplying rod-like articles, particularly filter-tipped cigarettes from one or more cigarette-making machines to one or more packing machines, said buffer magazines comprising a conveyor belt of reversible type and including a horizontal stretch carrying the cigarettes arranged crosswise thereto in superposed layers, and moving between two vertical side walls on a supporting table, said horizontal cigarette-carrying stretch having fixed thereto a transverse partition wall extending upwardly between the two side walls and moving, through corresponding movements of the conveyor belt, alternately away from the inlet of the magazine (located at one end of the cigarette-carrying stretch of said conveyor belt) to increase the capacity of the magazine and store cigarettes, and toward the inlet of said magazine to reduce the capacity of the magazine and return said stored cigarettes.
When the magazines of the type specified above receive filter-tipped cigarettes, the various layers of cigarettes on the horizontal cigarette-carrying stretch of the conveyor belt are inclined transversely to said conveyor belt because the filter-equipped end of each cigarette has a slightly larger diameter than the opposed end that is not provided with a filter. Inasmuch as the filter-tipped cigarettes of all the layers of cigarettes in the buffer magazine are directed in the same direction, the farther from the base (or horizontal cigarette-carrying stretch) they are, the steeper is their inclination transversely to the conveyor belt. When many layers of cigarettes are built up, the inclined cigarettes, especially in the upper layers, could slip down and fret with their ends remote from the filters against the respective vertical side wall of the buffer magazine. This fretting is also induced by possible side-skid movements of the horizontal cigarette-carrying stretch of the conveyor belt, said side-skid movements occurring more frequently upon changes of direction of the conveyor belt. The fretting of the lower ends of the inclined cigarettes against the respective side wall of the buffer magazine could damage the cigarettes and could brake the respective ends of the cigarettes during the longitudinal filling and emptying movements of the buffer magazine to such an extent as to turn the cigarettes askew or parallel to the longitudinal direction of the conveyor belt, with resulting disturbance in the operation.
This invention avoids this drawback by providing a supporting table, for the horizontal cigarette-carrying stretch of the conveyor belt, which is inclined or adapted to be inclined with respect to the horizontal transversely to the longitudinal direction of said cigarette-carrying stretch, and oppositely to the transverse inclination which the filter-tipped cigarettes tend to assume on said cigarette-carrying stretch, so as to ensure an average compensation for said inclination and to eliminate or at least minimize the inclination of the cigarettes in the upper layers.
Preferably, the transverse inclination of the supporting table for the horizontal cigarette-carrying stretch is regulatable to suit the changing inclination of the filter-tipped cigarettes and/or the number of superposed layers of filter-tipped cigarettes stored in the buffer magazine, or to arrange said supporting table horizontally when the buffer magazine is to receive cigarettes with no filter, which cigarettes will not become inclined transversely to the conveyor belt.
The invention provides also guide means to avoid any side skid or tilt of the cigarette-carrying stretch of the conveyor belt with respect to the supporting table even when the latter is inclined. In a preferred embodiment, said guide means comprises at least one longitudinal rib on the undersurface of the cigarette-carrying stretch of the conveyor belt, which is engaged in a corresponding longitudinal groove in the upper surface of the supporting table, or vice-versa.
According to another feature of the invention, the transverse partition wall fixed to the horizontal cigarette-carrying stretch of the conveyor belt is movable therewith, is pivotably connected to said belt on an axis extending longitudinally thereof, whereby it can be inclined transversely to the conveyor belt oppositely to the transverse inclination of the supporting table so that its side edges can be maintained parallel to the two vertical side walls of the buffer magazine. This permits the use of a transverse partition wall of a width substantially corresponding to the distance between the two side walls of the magazine.
According to another feature of the invention, inasmuch as the transverse inclination of the supporting wall causes a corresponding inclination of the horizontal cigarette-carrying stretch of the conveyor belt, at least the direction-changing roller for said belt at the inlet of the buffer magazine is also adapted to be inclined transversely similarly to the supporting wall.
These and other features of the invention and the advantages resulting therefrom will be apparent from the following description of a preferred embodiment thereof, shown by way of non-limitating example in the accompanying drawings, wherein: